my boy drinking capacity siao siao one..sometimes as little as 70ml, sometimes he good mood, as much as 180...zzz...thats y i worry y so messy...but my mom always tell me , don force , don force...hee.....drink more, longer time lo, drink less, shorter timing lo..so is the same....180ML = 3.5hrs for my boy..sometimes 3hrs..then he drink lesser at that feed.